<!DOCTYPE html>
<html lang="zh-CN">
  <head>
  <meta charset="UTF-8">
  <meta 
    name="viewport"
    content="width=device-width, initial-scale=1.0, minimum-scale=1.0">
  <meta 
    http-equiv="X-UA-Compatible" 
    content="ie=edge">
  <meta 
    name="theme-color" 
    content="#fff" 
    id="theme-color">
  <meta 
    name="description" 
    content="hexoDemo用于介绍如何使用hexo">
  <link 
    rel="icon" 
    href="/">
  <title>04-CSS选择器：伪类</title>
  
    
      <meta 
        property="og:title" 
        content="04-CSS选择器：伪类">
    
    
      <meta 
        property="og:url" 
        content="https://zwl5670.gitee.io/2002/01/01/02-CSS%E5%9F%BA%E7%A1%80/04-CSS%E9%80%89%E6%8B%A9%E5%99%A8%EF%BC%9A%E4%BC%AA%E7%B1%BB/index.html">
    
    
      <meta 
        property="og:img" 
        content="https://img.songhn.com/img/Y67gdd.png">
    
    
      <meta 
        property="og:img" 
        content="hexoDemo用于介绍如何使用hexo">
    
    
      <meta 
        property="og:type" 
        content="article">
      <meta 
        property="og:article:published_time" 
        content="2002-01-01">
      <meta 
        property="og:article:modified_time" 
        content="2023-03-14">
      <meta 
        property="og:article:author" 
        content="zwl5670">
      
        
          <meta 
            property="og:article:tag" 
            content="CSS基础">
        
      
    
  
  
  <link rel="preload" href="//at.alicdn.com/t/font_1946621_i1kgafibvw.css" as="style" >
  <link rel="preload" href="//at.alicdn.com/t/font_1952792_89b4ac4k4up.css" as="style" >
  <link rel="preload" href="/css/main.css" as="style" >
  
  <link rel="modulepreload" href="//instant.page/5.1.0">
  
  <link rel="stylesheet" href="/css/main.css">
  
  <link rel="stylesheet" href="//at.alicdn.com/t/font_1946621_i1kgafibvw.css">
  
  <link rel="stylesheet" href="//at.alicdn.com/t/font_1952792_89b4ac4k4up.css">
  
  
  
    <link rel="stylesheet" href="/js/lib/lightbox/baguetteBox.min.css">
  
  <script>
    function loadScript(url, cb) {
      var script = document.createElement('script');
      script.src = url;
      if (cb) script.onload = cb;
      script.async = true;
      document.body.appendChild(script);
    }
    function loadCSS(href, data, attr) {
      var sheet = document.createElement('link');
      sheet.ref = 'stylesheet';
      sheet.href = href;
      sheet.dataset[data] = attr;
      document.head.appendChild(sheet);
    }
    function changeCSS(cssFile, data, attr) {
      var oldlink = document.querySelector(data);
      var newlink = document.createElement("link");
      newlink.setAttribute("rel", "stylesheet");
      newlink.setAttribute("href", cssFile);
      newlink.dataset.prism = attr;
      document.head.replaceChild(newlink, oldlink);
    }
  </script>
  
    
  
  <script>
    // control reverse button
    var reverseDarkList = {
      dark: 'light',
      light: 'dark'
    };
    var themeColor = {
      dark: '#1c1c1e',
      light: '#fff'
    }
    // get the data of css prefers-color-scheme
    var getCssMediaQuery = function() {
      return window.matchMedia('(prefers-color-scheme: dark)').matches ? 'dark' : 'light';
    };
    // reverse current darkmode setting function
    var reverseDarkModeSetting = function() {
      var setting = localStorage.getItem('user-color-scheme');
      if(reverseDarkList[setting]) {
        setting = reverseDarkList[setting];
      } else if(setting === null) {
        setting = reverseDarkList[getCssMediaQuery()];
      } else {
        return;
      }
      localStorage.setItem('user-color-scheme', setting);
      return setting;
    };
    // apply current darkmode setting
  </script>
  
    <script>
      var setDarkmode = function(mode) {
      var setting = mode || localStorage.getItem('user-color-scheme');
      if(setting === getCssMediaQuery()) {
        document.documentElement.removeAttribute('data-user-color-scheme');
        localStorage.removeItem('user-color-scheme');
        document.getElementById('theme-color').content = themeColor[setting];
        document.getElementById('theme-color').dataset.mode = setting;
      } else if(reverseDarkList[setting]) {
        document.documentElement.setAttribute('data-user-color-scheme', setting);
        document.getElementById('theme-color').content = themeColor[setting];
        document.getElementById('theme-color').dataset.mode = setting;
      } else {
        document.documentElement.removeAttribute('data-user-color-scheme');
        localStorage.removeItem('user-color-scheme');
        document.getElementById('theme-color').content = themeColor[getCssMediaQuery()];
        document.getElementById('theme-color').dataset.mode = getCssMediaQuery();
      }
    };
    setDarkmode();
    </script>
  
  
  
    <link rel="preload" href="/js/lib/lightbox/baguetteBox.min.js" as="script">
    <link rel="preload" href="/js/lib/lightbox/baguetteBox.min.css" as="style" >
  
  
    <link rel="preload" href="/js/lib/lozad.min.js" as="script">
  
  
  
  
  
  
<meta name="generator" content="Hexo 6.3.0"></head>

  <body>
    <div class="wrapper">
       
      <nav class="navbar">
  <div class="navbar-logo">
    <a class="navbar-logo-main" href="/">
      
      <span class="navbar-logo-dsc">前端面试</span>
      </a>
  </div>
  <div class="navbar-menu">
    
      <a 
        href="/" 
        class="navbar-menu-item">
        
          首页
        
      </a>
    
      <a 
        href="/archives" 
        class="navbar-menu-item">
        
          归档
        
      </a>
    
      <a 
        href="/tags" 
        class="navbar-menu-item">
        
          标签
        
      </a>
    
      <a 
        href="/categories" 
        class="navbar-menu-item">
        
          分类
        
      </a>
    
      <a 
        href="/about" 
        class="navbar-menu-item">
        
          关于
        
      </a>
    
      <a 
        href="/links" 
        class="navbar-menu-item">
        
          友链
        
      </a>
    
    <button 
      class="navbar-menu-item darknavbar navbar-menu-btn" 
      aria-label="Toggle dark mode"
      id="dark">
      <i class="iconfont icon-weather"></i>
    </button>
    <button 
      class="navbar-menu-item searchnavbar navbar-menu-btn" 
      aria-label="Toggle search"
      id="search">
      <!-- <i 
        class="iconfont icon-search" 
        style="font-size: 1.2rem; font-weight: 400;">
      </i> -->
      <svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img"
        class="iconify iconify--ion" width="28" height="28" preserveAspectRatio="xMidYMid meet" viewBox="0 0 512 512">
        <path fill="none" stroke="currentColor" stroke-miterlimit="10" stroke-width="28"
          d="M256 80a176 176 0 1 0 176 176A176 176 0 0 0 256 80Z"></path>
        <path fill="none" stroke="currentColor" stroke-miterlimit="10" stroke-width="28"
          d="M232 160a72 72 0 1 0 72 72a72 72 0 0 0-72-72Z"></path>
        <path fill="none" stroke="currentColor" stroke-linecap="round" stroke-miterlimit="10" stroke-width="28"
          d="M283.64 283.64L336 336"></path>
      </svg>
    </button>
  </div>
</nav> 
      
      <div 
        id="local-search" 
        style="display: none">
        <input
          class="navbar-menu-item"
          id="search-input"
          placeholder="请输入搜索内容..." />
        <div id="search-content"></div>
      </div>
      
      <div class="section-wrap">
        <div class="container">
          <div class="columns">
            <aside class="left-column">
              
              <div class="card card-author">
                
  <img 
    src="https://img.songhn.com/img/Y67gdd.png" 
    class="author-img"
    width="88"
    height="88"
    alt="author avatar">

<p class="author-name">zwl5670</p>
<p class="author-description">前端学习资料</p>
<div class="author-message">
  <a 
    class="author-posts-count" 
    href="/archives">
    <span>215</span>
    <span>文章</span>
  </a>
  <a 
    class="author-categories-count" 
    href="/categories">
    <span>14</span>
    <span>分类</span>
  </a>
  <a 
    class="author-tags-count" 
    href="/tags">
    <span>14</span>
    <span>标签</span>
  </a>
</div>

              </div>
               <div class="sticky-tablet">
  
  
    <article class="display-when-two-columns spacer">
      <div class="card card-content toc-card">
        <div class="toc-header">
  <i 
    class="iconfont icon-menu" 
    style="padding-right: 2px;">
  </i>目录
</div>
<ol class="toc"><li class="toc-item toc-level-2"><a class="toc-link" href="#%E4%BC%AA%E7%B1%BB%EF%BC%88%E4%BC%AA%E7%B1%BB%E9%80%89%E6%8B%A9%E5%99%A8%EF%BC%89"><span class="toc-text">伪类（伪类选择器）</span></a><ol class="toc-child"><li class="toc-item toc-level-3"><a class="toc-link" href="#%E9%9D%99%E6%80%81%E4%BC%AA%E7%B1%BB%E9%80%89%E6%8B%A9%E5%99%A8%E3%80%81%E5%8A%A8%E6%80%81%E4%BC%AA%E7%B1%BB%E9%80%89%E6%8B%A9%E5%99%A8"><span class="toc-text">静态伪类选择器、动态伪类选择器</span></a></li></ol></li><li class="toc-item toc-level-2"><a class="toc-link" href="#%E8%B6%85%E9%93%BE%E6%8E%A5a%E6%A0%87%E7%AD%BE"><span class="toc-text">超链接a标签</span></a><ol class="toc-child"><li class="toc-item toc-level-3"><a class="toc-link" href="#%E8%B6%85%E9%93%BE%E6%8E%A5%E7%9A%84%E5%9B%9B%E7%A7%8D%E7%8A%B6%E6%80%81"><span class="toc-text">超链接的四种状态</span></a></li><li class="toc-item toc-level-3"><a class="toc-link" href="#%E8%B6%85%E9%93%BE%E6%8E%A5%E7%9A%84%E7%BE%8E%E5%8C%96"><span class="toc-text">超链接的美化</span></a></li></ol></li><li class="toc-item toc-level-2"><a class="toc-link" href="#%E5%8A%A8%E6%80%81%E4%BC%AA%E7%B1%BB%E4%B8%BE%E4%BE%8B"><span class="toc-text">动态伪类举例</span></a></li><li class="toc-item toc-level-2"><a class="toc-link" href="#%E6%88%91%E7%9A%84%E5%85%AC%E4%BC%97%E5%8F%B7"><span class="toc-text">我的公众号</span></a></li></ol>
      </div>
    </article>
  
  
  <article class="card card-content categories-widget">
    <div class="categories-card">
  <div class="categories-header">
    <i 
      class="iconfont icon-fenlei" 
      style="padding-right: 2px;">
    </i>分类
  </div>
  <div class="categories-list">
    
      <a href="/categories/%E5%89%8D%E7%AB%AF%E5%B7%A5%E5%85%B7/">
        <div class="categories-list-item">
          前端工具
          <span class="categories-list-item-badge">13</span>
        </div>
      </a>
    
      <a href="/categories/CSS%E5%9F%BA%E7%A1%80/">
        <div class="categories-list-item">
          CSS基础
          <span class="categories-list-item-badge">18</span>
        </div>
      </a>
    
      <a href="/categories/CSS%E8%BF%9B%E9%98%B6/">
        <div class="categories-list-item">
          CSS进阶
          <span class="categories-list-item-badge">9</span>
        </div>
      </a>
    
      <a href="/categories/HTML/">
        <div class="categories-list-item">
          HTML
          <span class="categories-list-item-badge">12</span>
        </div>
      </a>
    
      <a href="/categories/JS%E5%9F%BA%E7%A1%80/">
        <div class="categories-list-item">
          JS基础
          <span class="categories-list-item-badge">56</span>
        </div>
      </a>
    
      <a href="/categories/JS%E5%9F%BA%E7%A1%80ES6/">
        <div class="categories-list-item">
          JS基础ES6
          <span class="categories-list-item-badge">10</span>
        </div>
      </a>
    
      <a href="/categories/JS%E5%9F%BA%E7%A1%80%E5%BC%82%E6%AD%A5/">
        <div class="categories-list-item">
          JS基础异步
          <span class="categories-list-item-badge">11</span>
        </div>
      </a>
    
      <a href="/categories/JS%E8%BF%9B%E9%98%B6/">
        <div class="categories-list-item">
          JS进阶
          <span class="categories-list-item-badge">11</span>
        </div>
      </a>
    
      <a href="/categories/%E7%A7%BB%E5%8A%A8web/">
        <div class="categories-list-item">
          移动web
          <span class="categories-list-item-badge">3</span>
        </div>
      </a>
    
      <a href="/categories/CSS%E5%92%8CDOM/">
        <div class="categories-list-item">
          CSS和DOM
          <span class="categories-list-item-badge">6</span>
        </div>
      </a>
    
      <a href="/categories/Node/">
        <div class="categories-list-item">
          Node
          <span class="categories-list-item-badge">16</span>
        </div>
      </a>
    
      <a href="/categories/Vue%E5%9F%BA%E7%A1%80/">
        <div class="categories-list-item">
          Vue基础
          <span class="categories-list-item-badge">15</span>
        </div>
      </a>
    
      <a href="/categories/%E6%80%A7%E8%83%BD%E4%BC%98%E5%8C%96/">
        <div class="categories-list-item">
          性能优化
          <span class="categories-list-item-badge">7</span>
        </div>
      </a>
    
      <a href="/categories/%E5%89%8D%E7%AB%AF%E5%B7%A5%E7%A8%8B%E5%8C%96/">
        <div class="categories-list-item">
          前端工程化
          <span class="categories-list-item-badge">8</span>
        </div>
      </a>
    
  </div>
</div>
  </article>
  
  <article class="card card-content tags-widget">
    <div class="tags-card">
  <div class="tags-header">
    <i 
      class="iconfont icon-biaoqian" 
      style="padding-right: 2px;">
    </i>热门标签
  </div>
  <div class="tags-list">
    
      <a 
        href="/tags/JS%E5%9F%BA%E7%A1%80/" 
        title="JS基础">
        <div class="tags-list-item">JS基础</div>
      </a>
    
      <a 
        href="/tags/CSS%E5%9F%BA%E7%A1%80/" 
        title="CSS基础">
        <div class="tags-list-item">CSS基础</div>
      </a>
    
      <a 
        href="/tags/Node/" 
        title="Node">
        <div class="tags-list-item">Node</div>
      </a>
    
      <a 
        href="/tags/Vue%E5%9F%BA%E7%A1%80/" 
        title="Vue基础">
        <div class="tags-list-item">Vue基础</div>
      </a>
    
      <a 
        href="/tags/%E5%89%8D%E7%AB%AF%E5%B7%A5%E5%85%B7/" 
        title="前端工具">
        <div class="tags-list-item">前端工具</div>
      </a>
    
      <a 
        href="/tags/HTML/" 
        title="HTML">
        <div class="tags-list-item">HTML</div>
      </a>
    
      <a 
        href="/tags/JS%E8%BF%9B%E9%98%B6/" 
        title="JS进阶">
        <div class="tags-list-item">JS进阶</div>
      </a>
    
      <a 
        href="/tags/JS%E5%9F%BA%E7%A1%80%E5%BC%82%E6%AD%A5/" 
        title="JS基础异步">
        <div class="tags-list-item">JS基础异步</div>
      </a>
    
      <a 
        href="/tags/JS%E5%9F%BA%E7%A1%80ES6/" 
        title="JS基础ES6">
        <div class="tags-list-item">JS基础ES6</div>
      </a>
    
      <a 
        href="/tags/CSS%E8%BF%9B%E9%98%B6/" 
        title="CSS进阶">
        <div class="tags-list-item">CSS进阶</div>
      </a>
    
      <a 
        href="/tags/%E5%89%8D%E7%AB%AF%E5%B7%A5%E7%A8%8B%E5%8C%96/" 
        title="前端工程化">
        <div class="tags-list-item">前端工程化</div>
      </a>
    
      <a 
        href="/tags/%E6%80%A7%E8%83%BD%E4%BC%98%E5%8C%96/" 
        title="性能优化">
        <div class="tags-list-item">性能优化</div>
      </a>
    
      <a 
        href="/tags/CSS%E5%92%8CDOM/" 
        title="CSS和DOM">
        <div class="tags-list-item">CSS和DOM</div>
      </a>
    
      <a 
        href="/tags/%E7%A7%BB%E5%8A%A8web/" 
        title="移动web">
        <div class="tags-list-item">移动web</div>
      </a>
    
  </div>
</div>
  </article>
  
  
</div>
            </aside>
            <main class="main-column">
              
<article class="card card-content">
  <header>
    <h1 class="post-title">
      04-CSS选择器：伪类
    </h1>
  </header>
  <div class="post-meta post-show-meta">
    <time datetime="2001-12-31T16:00:00.000Z">
      <i 
        class="iconfont icon-calendar" 
        style="margin-right: 2px;">
      </i>
      <span>2002-01-01</span>
    </time>
    
      <span class="dot"></span>
      
        <a 
          href="/categories/CSS%E5%9F%BA%E7%A1%80/" 
          class="post-meta-link">
          CSS基础
        </a>
      
    
    
      <span class="dot"></span>
      <span>1.9k 字</span>
    
  </div>
  
    <div 
      class="post-meta post-show-meta" 
      style="margin-top: -10px;">
      <div style="display: flex; align-items: center;">
        <i 
          class="iconfont icon-biaoqian" 
          style="margin-right: 2px; font-size: 1.15rem;">
        </i>
        
          
          <a 
            href="/tags/CSS%E5%9F%BA%E7%A1%80/" 
            class="post-meta-link">
            CSS基础
          </a>
        
      </div>
    </div>
  
  </header>
  <div 
    id="section" 
    class="post-content">
    <p><ArticleTopAd></ArticleTopAd></p>
<h2 id="伪类（伪类选择器）"><a href="#伪类（伪类选择器）" class="headerlink" title="伪类（伪类选择器）"></a>伪类（伪类选择器）</h2><p><strong>伪类</strong>：同一个标签，根据其<strong>不同的种状态，有不同的样式</strong>。这就叫做“伪类”。伪类用冒号来表示。</p>
<p>比如div是属于box类，这一点很明确，就是属于box类。但是a属于什么类？不明确。因为需要看用户点击前是什么状态，点击后是什么状态。所以，就叫做“伪类”。</p>
<h3 id="静态伪类选择器、动态伪类选择器"><a href="#静态伪类选择器、动态伪类选择器" class="headerlink" title="静态伪类选择器、动态伪类选择器"></a>静态伪类选择器、动态伪类选择器</h3><p>伪类选择器分为两种。</p>
<p>（1）<strong>静态伪类</strong>：只能用于<strong>超链接</strong>的样式。如下：</p>
<ul>
<li><code>:link</code> 超链接点击之前</li>
<li><code>:visited</code> 链接被访问过之后</li>
</ul>
<p>PS：以上两种样式，只能用于超链接。</p>
<p>（2）<strong>动态伪类</strong>：针对<strong>所有标签</strong>都适用的样式。如下：</p>
<ul>
<li><code>:hover</code> “悬停”：鼠标放到标签上的时候</li>
<li><code>:active</code>	“激活”： 鼠标点击标签，但是不松手时。</li>
<li><code>:focus</code> 是某个标签获得焦点时的样式（比如某个输入框获得焦点）</li>
</ul>
<h2 id="超链接a标签"><a href="#超链接a标签" class="headerlink" title="超链接a标签"></a>超链接a标签</h2><h3 id="超链接的四种状态"><a href="#超链接的四种状态" class="headerlink" title="超链接的四种状态"></a>超链接的四种状态</h3><p>a标签有4种伪类（即对应四种状态），要求背诵。如下：</p>
<ul>
<li><code>:link</code>  	“链接”：超链接点击之前</li>
<li><code>:visited</code> “访问过的”：链接被访问过之后</li>
<li><code>:hover</code>	“悬停”：鼠标放到标签上的时候</li>
<li><code>:active</code>	“激活”： 鼠标点击标签，但是不松手时。</li>
</ul>
<p>对应的代码如下：</p>
<pre class="highlight"><span class="line"><span class="tag">&lt;<span class="name">style</span> <span class="attr">type</span>=<span class="string">&quot;text/css&quot;</span>&gt;</span><span class="language-css"></span></span><br><span class="line"><span class="language-css">	<span class="comment">/*让超链接点击之前是红色*/</span></span></span><br><span class="line"><span class="language-css">	<span class="selector-tag">a</span><span class="selector-pseudo">:link</span>&#123;</span></span><br><span class="line"><span class="language-css">		<span class="attribute">color</span>:red;</span></span><br><span class="line"><span class="language-css">	&#125;</span></span><br><span class="line"><span class="language-css"></span></span><br><span class="line"><span class="language-css">	<span class="comment">/*让超链接点击之后是绿色*/</span></span></span><br><span class="line"><span class="language-css">	<span class="selector-tag">a</span><span class="selector-pseudo">:visited</span>&#123;</span></span><br><span class="line"><span class="language-css">		<span class="attribute">color</span>:orange;</span></span><br><span class="line"><span class="language-css">	&#125;</span></span><br><span class="line"><span class="language-css"></span></span><br><span class="line"><span class="language-css">	<span class="comment">/*鼠标悬停，放到标签上的时候*/</span></span></span><br><span class="line"><span class="language-css">	<span class="selector-tag">a</span><span class="selector-pseudo">:hover</span>&#123;</span></span><br><span class="line"><span class="language-css">		<span class="attribute">color</span>:green;</span></span><br><span class="line"><span class="language-css">	&#125;</span></span><br><span class="line"><span class="language-css"></span></span><br><span class="line"><span class="language-css">	<span class="comment">/*鼠标点击链接，但是不松手的时候*/</span></span></span><br><span class="line"><span class="language-css">	<span class="selector-tag">a</span><span class="selector-pseudo">:active</span>&#123;</span></span><br><span class="line"><span class="language-css">		<span class="attribute">color</span>:black;</span></span><br><span class="line"><span class="language-css">	&#125;</span></span><br><span class="line"><span class="language-css"></span><span class="tag">&lt;/<span class="name">style</span>&gt;</span></span><br></pre>


<p>记住，在css中，这四种状态<strong>必须按照固定的顺序写</strong>：</p>
<blockquote>
<p>a:link 、a:visited 、a:hover 、a:active</p>
</blockquote>
<p>如果不按照顺序，那么将失效。“爱恨准则”：love hate。必须先爱，后恨。</p>
<p>看一下这四种状态的动图效果：</p>
<p><img  srcset="data:image/svg+xml,%3Csvg%20xmlns='http://www.w3.org/2000/svg'%20viewBox='0%200%20300%20300'%3E%3C/svg%3E" data-src="http://img.smyhvae.com/20180113_2239.gif" class="lozad post-image"src="http://img.smyhvae.com/20180113_2239.gif"></p>
<h3 id="超链接的美化"><a href="#超链接的美化" class="headerlink" title="超链接的美化"></a>超链接的美化</h3><p>问：既然<code>a&#123;&#125;</code>定义了超链的属性，和<code>a:link&#123;&#125;</code>定义了超链点击之前的属性，那这两个有啥区别呢？</p>
<p>答：</p>
<p><strong><code>a&#123;&#125;</code>和<code>a:link&#123;&#125;</code>的区别：</strong></p>
<ul>
<li><code>a&#123;&#125;</code>定义的样式针对所有的超链接(包括锚点)</li>
<li><code>a:link&#123;&#125;</code>定义的样式针对所有写了href属性的超链接(不包括锚点)</li>
</ul>
<p>超链接a标签在使用的时候，比较难。因为不仅仅要控制a这个盒子，也要控制它的伪类。</p>
<p>我们一定要将a标签写在前面，将<code>:link、:visited、:hover、:active</code>这些伪类写在后面。</p>
<p>针对超链接，我们来举个例子：</p>
<p><img  srcset="data:image/svg+xml,%3Csvg%20xmlns='http://www.w3.org/2000/svg'%20viewBox='0%200%20300%20300'%3E%3C/svg%3E" data-src="http://img.smyhvae.com/20170810_2235.gif" class="lozad post-image"src="http://img.smyhvae.com/20170810_2235.gif"></p>
<p>为了实现上面这个效果，完整版代码如下：</p>
<pre class="highlight"><span class="line"><span class="meta">&lt;!DOCTYPE <span class="keyword">html</span> <span class="keyword">PUBLIC</span> <span class="string">&quot;-//W3C//DTD XHTML 1.0 Transitional//EN&quot;</span> <span class="string">&quot;http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd&quot;</span>&gt;</span></span><br><span class="line"><span class="tag">&lt;<span class="name">html</span> <span class="attr">xmlns</span>=<span class="string">&quot;http://www.w3.org/1999/xhtml&quot;</span> <span class="attr">xml:lang</span>=<span class="string">&quot;en&quot;</span>&gt;</span></span><br><span class="line"><span class="tag">&lt;<span class="name">head</span>&gt;</span></span><br><span class="line">	<span class="tag">&lt;<span class="name">meta</span> <span class="attr">http-equiv</span>=<span class="string">&quot;Content-Type&quot;</span> <span class="attr">content</span>=<span class="string">&quot;text/html;charset=UTF-8&quot;</span>&gt;</span></span><br><span class="line">	<span class="tag">&lt;<span class="name">title</span>&gt;</span>Document<span class="tag">&lt;/<span class="name">title</span>&gt;</span></span><br><span class="line">	<span class="tag">&lt;<span class="name">style</span> <span class="attr">type</span>=<span class="string">&quot;text/css&quot;</span>&gt;</span><span class="language-css"></span></span><br><span class="line"><span class="language-css">		*&#123;</span></span><br><span class="line"><span class="language-css">			<span class="attribute">margin</span>: <span class="number">0</span>;</span></span><br><span class="line"><span class="language-css">			<span class="attribute">padding</span>: <span class="number">0</span>;</span></span><br><span class="line"><span class="language-css">		&#125;</span></span><br><span class="line"><span class="language-css">		<span class="selector-class">.nav</span>&#123;</span></span><br><span class="line"><span class="language-css">			<span class="attribute">width</span>: <span class="number">960px</span>;</span></span><br><span class="line"><span class="language-css">			<span class="attribute">height</span>: <span class="number">50px</span>;</span></span><br><span class="line"><span class="language-css">			<span class="attribute">border</span>: <span class="number">1px</span> solid red;</span></span><br><span class="line"><span class="language-css">			<span class="attribute">margin</span>: <span class="number">100px</span> auto;</span></span><br><span class="line"><span class="language-css">		&#125;</span></span><br><span class="line"><span class="language-css">		<span class="selector-class">.nav</span> <span class="selector-tag">ul</span>&#123;</span></span><br><span class="line"><span class="language-css">			<span class="comment">/*去掉小圆点*/</span></span></span><br><span class="line"><span class="language-css">			<span class="attribute">list-style</span>: none;</span></span><br><span class="line"><span class="language-css">		&#125;</span></span><br><span class="line"><span class="language-css">		<span class="selector-class">.nav</span> <span class="selector-tag">ul</span> <span class="selector-tag">li</span>&#123;</span></span><br><span class="line"><span class="language-css">			<span class="attribute">float</span>: left;</span></span><br><span class="line"><span class="language-css">			<span class="attribute">width</span>: <span class="number">120px</span>;</span></span><br><span class="line"><span class="language-css">			<span class="attribute">height</span>: <span class="number">50px</span>;</span></span><br><span class="line"><span class="language-css">			<span class="comment">/*让内容水平居中*/</span></span></span><br><span class="line"><span class="language-css">			<span class="attribute">text-align</span>: center;</span></span><br><span class="line"><span class="language-css">			<span class="comment">/*让行高等于nav的高度，就可以保证内容垂直居中*/</span></span></span><br><span class="line"><span class="language-css">			<span class="attribute">line-height</span>: <span class="number">50px</span>;</span></span><br><span class="line"><span class="language-css">		&#125;</span></span><br><span class="line"><span class="language-css">		<span class="selector-class">.nav</span> <span class="selector-tag">ul</span> <span class="selector-tag">li</span> <span class="selector-tag">a</span>&#123;</span></span><br><span class="line"><span class="language-css">			<span class="attribute">display</span>: block;</span></span><br><span class="line"><span class="language-css">			<span class="attribute">width</span>: <span class="number">120px</span>;</span></span><br><span class="line"><span class="language-css">			<span class="attribute">height</span>: <span class="number">50px</span>;</span></span><br><span class="line"><span class="language-css">		&#125;</span></span><br><span class="line"><span class="language-css">		<span class="comment">/*两个伪类的属性，可以用逗号隔开*/</span></span></span><br><span class="line"><span class="language-css">		<span class="selector-class">.nav</span> <span class="selector-tag">ul</span> <span class="selector-tag">li</span> <span class="selector-tag">a</span><span class="selector-pseudo">:link</span> , <span class="selector-class">.nav</span> <span class="selector-tag">ul</span> <span class="selector-tag">li</span> <span class="selector-tag">a</span><span class="selector-pseudo">:visited</span>&#123;</span></span><br><span class="line"><span class="language-css">			<span class="attribute">text-decoration</span>: none;</span></span><br><span class="line"><span class="language-css">			<span class="attribute">background-color</span>: purple;</span></span><br><span class="line"><span class="language-css">			<span class="attribute">color</span>:white;</span></span><br><span class="line"><span class="language-css">		&#125;</span></span><br><span class="line"><span class="language-css">		<span class="selector-class">.nav</span> <span class="selector-tag">ul</span> <span class="selector-tag">li</span> <span class="selector-tag">a</span><span class="selector-pseudo">:hover</span>&#123;</span></span><br><span class="line"><span class="language-css">			<span class="attribute">background-color</span>: orange;</span></span><br><span class="line"><span class="language-css">		&#125;</span></span><br><span class="line"><span class="language-css">	</span><span class="tag">&lt;/<span class="name">style</span>&gt;</span></span><br><span class="line"><span class="tag">&lt;/<span class="name">head</span>&gt;</span></span><br><span class="line"><span class="tag">&lt;<span class="name">body</span>&gt;</span></span><br><span class="line">	<span class="tag">&lt;<span class="name">div</span> <span class="attr">class</span>=<span class="string">&quot;nav&quot;</span>&gt;</span></span><br><span class="line">		<span class="tag">&lt;<span class="name">ul</span>&gt;</span></span><br><span class="line">			<span class="tag">&lt;<span class="name">li</span>&gt;</span><span class="tag">&lt;<span class="name">a</span> <span class="attr">href</span>=<span class="string">&quot;#&quot;</span>&gt;</span>网站栏目<span class="tag">&lt;/<span class="name">a</span>&gt;</span><span class="tag">&lt;/<span class="name">li</span>&gt;</span></span><br><span class="line">			<span class="tag">&lt;<span class="name">li</span>&gt;</span><span class="tag">&lt;<span class="name">a</span> <span class="attr">href</span>=<span class="string">&quot;#&quot;</span>&gt;</span>网站栏目<span class="tag">&lt;/<span class="name">a</span>&gt;</span><span class="tag">&lt;/<span class="name">li</span>&gt;</span></span><br><span class="line">			<span class="tag">&lt;<span class="name">li</span>&gt;</span><span class="tag">&lt;<span class="name">a</span> <span class="attr">href</span>=<span class="string">&quot;#&quot;</span>&gt;</span>网站栏目<span class="tag">&lt;/<span class="name">a</span>&gt;</span><span class="tag">&lt;/<span class="name">li</span>&gt;</span></span><br><span class="line">			<span class="tag">&lt;<span class="name">li</span>&gt;</span><span class="tag">&lt;<span class="name">a</span> <span class="attr">href</span>=<span class="string">&quot;#&quot;</span>&gt;</span>网站栏目<span class="tag">&lt;/<span class="name">a</span>&gt;</span><span class="tag">&lt;/<span class="name">li</span>&gt;</span></span><br><span class="line">			<span class="tag">&lt;<span class="name">li</span>&gt;</span><span class="tag">&lt;<span class="name">a</span> <span class="attr">href</span>=<span class="string">&quot;#&quot;</span>&gt;</span>网站栏目<span class="tag">&lt;/<span class="name">a</span>&gt;</span><span class="tag">&lt;/<span class="name">li</span>&gt;</span></span><br><span class="line">			<span class="tag">&lt;<span class="name">li</span>&gt;</span><span class="tag">&lt;<span class="name">a</span> <span class="attr">href</span>=<span class="string">&quot;#&quot;</span>&gt;</span>网站栏目<span class="tag">&lt;/<span class="name">a</span>&gt;</span><span class="tag">&lt;/<span class="name">li</span>&gt;</span></span><br><span class="line">			<span class="tag">&lt;<span class="name">li</span>&gt;</span><span class="tag">&lt;<span class="name">a</span> <span class="attr">href</span>=<span class="string">&quot;#&quot;</span>&gt;</span>网站栏目<span class="tag">&lt;/<span class="name">a</span>&gt;</span><span class="tag">&lt;/<span class="name">li</span>&gt;</span></span><br><span class="line">			<span class="tag">&lt;<span class="name">li</span>&gt;</span><span class="tag">&lt;<span class="name">a</span> <span class="attr">href</span>=<span class="string">&quot;#&quot;</span>&gt;</span>网站栏目<span class="tag">&lt;/<span class="name">a</span>&gt;</span><span class="tag">&lt;/<span class="name">li</span>&gt;</span></span><br><span class="line">		<span class="tag">&lt;/<span class="name">ul</span>&gt;</span></span><br><span class="line">	<span class="tag">&lt;/<span class="name">div</span>&gt;</span></span><br><span class="line"><span class="tag">&lt;/<span class="name">body</span>&gt;</span></span><br><span class="line"><span class="tag">&lt;/<span class="name">html</span>&gt;</span></span><br></pre>

<p>上方代码中，我们发现，当我们在定义<code>a:link</code>和 <code>a:visited</code>这两个伪类的时候，如果它们的属性相同，我们其实可以写在一起，用逗号隔开就好，摘抄如下：</p>
<pre class="highlight"><span class="line"><span class="selector-class">.nav</span> <span class="selector-tag">ul</span> <span class="selector-tag">li</span> <span class="selector-tag">a</span>&#123;</span><br><span class="line">	<span class="attribute">display</span>: block;</span><br><span class="line">	<span class="attribute">width</span>: <span class="number">120px</span>;</span><br><span class="line">	<span class="attribute">height</span>: <span class="number">50px</span>;</span><br><span class="line">&#125;</span><br><span class="line"><span class="comment">/*两个伪类的属性，可以用逗号隔开*/</span></span><br><span class="line"><span class="selector-class">.nav</span> <span class="selector-tag">ul</span> <span class="selector-tag">li</span> <span class="selector-tag">a</span><span class="selector-pseudo">:link</span> , <span class="selector-class">.nav</span> <span class="selector-tag">ul</span> <span class="selector-tag">li</span> <span class="selector-tag">a</span><span class="selector-pseudo">:visited</span>&#123;</span><br><span class="line">	<span class="attribute">text-decoration</span>: none;</span><br><span class="line">	<span class="attribute">background-color</span>: purple;</span><br><span class="line">	<span class="attribute">color</span>:white;</span><br><span class="line">&#125;</span><br><span class="line"><span class="selector-class">.nav</span> <span class="selector-tag">ul</span> <span class="selector-tag">li</span> <span class="selector-tag">a</span><span class="selector-pseudo">:hover</span>&#123;</span><br><span class="line">	<span class="attribute">background-color</span>: orange;</span><br><span class="line">&#125;</span><br></pre>

<p>如上方代码所示，最标准的写法，就是把link、visited、hover这三个伪类都要写。但是前端开发工程师在大量的实践中，发现不写link、visited也挺兼容。写法是：</p>
<blockquote>
<p>a:link、a:visited都是可以省略的，简写在a标签里面。也就是说，a标签涵盖了link、visited的状态（前提是都具有了相同的属性）。写法如下：</p>
</blockquote>
<pre class="highlight"><span class="line"><span class="selector-class">.nav</span> <span class="selector-tag">ul</span> <span class="selector-tag">li</span> <span class="selector-tag">a</span>&#123;</span><br><span class="line">	<span class="attribute">display</span>: block;</span><br><span class="line">	<span class="attribute">width</span>: <span class="number">120px</span>;</span><br><span class="line">	<span class="attribute">height</span>: <span class="number">50px</span>;</span><br><span class="line">	<span class="attribute">text-decoration</span>: none;</span><br><span class="line">	<span class="attribute">background-color</span>: purple;</span><br><span class="line">	<span class="attribute">color</span>:white;</span><br><span class="line">&#125;</span><br><span class="line"><span class="selector-class">.nav</span> <span class="selector-tag">ul</span> <span class="selector-tag">li</span> <span class="selector-tag">a</span><span class="selector-pseudo">:hover</span>&#123;</span><br><span class="line">	<span class="attribute">background-color</span>: orange;</span><br><span class="line">&#125;</span><br><span class="line"></span><br></pre>

<p>当然了，在写<code>a:link</code>、<code>a:visited</code>这两个伪类的时候，要么同时写，要么同时不写。如果只写<code>a</code>属性和<code>a:link</code>属性，不规范。</p>
<h2 id="动态伪类举例"><a href="#动态伪类举例" class="headerlink" title="动态伪类举例"></a>动态伪类举例</h2><p>我们在第一段中描述过，下面这三种动态伪类，针对所有标签都适用。</p>
<ul>
<li><code>:hover</code> “悬停”：鼠标放到标签上的时候</li>
<li><code>:active</code>	“激活”： 鼠标点击标签，但是不松手时。</li>
<li><code>:focus</code> 是某个标签获得焦点时的样式（比如某个输入框获得焦点）</li>
</ul>
<p>我们不妨来举下例子。</p>
<p>举例1：</p>
<pre class="highlight"><span class="line"> <span class="tag">&lt;<span class="name">style</span> <span class="attr">type</span>=<span class="string">&quot;text/css&quot;</span>&gt;</span><span class="language-css"></span></span><br><span class="line"><span class="language-css"> <span class="comment">/*</span></span></span><br><span class="line"><span class="comment"><span class="language-css">伪类选择器：动态伪类</span></span></span><br><span class="line"><span class="comment"><span class="language-css"> */</span></span></span><br><span class="line"><span class="language-css"></span></span><br><span class="line"><span class="language-css">  <span class="comment">/*</span></span></span><br><span class="line"><span class="comment"><span class="language-css">让文本框获取焦点时：</span></span></span><br><span class="line"><span class="comment"><span class="language-css">边框：#FF6F3D这种橙色</span></span></span><br><span class="line"><span class="comment"><span class="language-css">文字：绿色</span></span></span><br><span class="line"><span class="comment"><span class="language-css">背景色：#6a6a6a这种灰色</span></span></span><br><span class="line"><span class="comment"><span class="language-css">  */</span></span></span><br><span class="line"><span class="language-css"><span class="selector-tag">input</span><span class="selector-pseudo">:focus</span>&#123;</span></span><br><span class="line"><span class="language-css">	<span class="attribute">border</span>:<span class="number">3px</span> solid <span class="number">#FF6F3D</span>;</span></span><br><span class="line"><span class="language-css">	<span class="attribute">color</span>:white;</span></span><br><span class="line"><span class="language-css">	<span class="attribute">background-color</span>:<span class="number">#6a6a6a</span>;</span></span><br><span class="line"><span class="language-css">&#125;</span></span><br><span class="line"><span class="language-css"></span></span><br><span class="line"><span class="language-css"><span class="comment">/*</span></span></span><br><span class="line"><span class="comment"><span class="language-css">鼠标放在标签上时显示蓝色</span></span></span><br><span class="line"><span class="comment"><span class="language-css">   */</span></span></span><br><span class="line"><span class="language-css"><span class="selector-tag">label</span><span class="selector-pseudo">:hover</span>&#123;</span></span><br><span class="line"><span class="language-css">	<span class="attribute">color</span>:blue;</span></span><br><span class="line"><span class="language-css">&#125;</span></span><br><span class="line"><span class="language-css"></span></span><br><span class="line"><span class="language-css"><span class="comment">/*</span></span></span><br><span class="line"><span class="comment"><span class="language-css">点击标签鼠标没有松开时显示红色</span></span></span><br><span class="line"><span class="comment"><span class="language-css">   */</span></span></span><br><span class="line"><span class="language-css"><span class="selector-tag">label</span><span class="selector-pseudo">:active</span>&#123;</span></span><br><span class="line"><span class="language-css">	<span class="attribute">color</span>:red;</span></span><br><span class="line"><span class="language-css">&#125;</span></span><br><span class="line"><span class="language-css"></span></span><br><span class="line"><span class="language-css"> </span><span class="tag">&lt;/<span class="name">style</span>&gt;</span></span><br></pre>

<p>效果：</p>
<p><img  srcset="data:image/svg+xml,%3Csvg%20xmlns='http://www.w3.org/2000/svg'%20viewBox='0%200%20300%20300'%3E%3C/svg%3E" data-src="http://img.smyhvae.com/2015-10-03-css-02.gif" class="lozad post-image"src="http://img.smyhvae.com/2015-10-03-css-02.gif"></p>
<p>利用这个<code>hover</code>属性，我们同样对表格做一个样式的设置：<br>表格举例：</p>
<pre class="highlight"><span class="line"><span class="meta">&lt;!doctype <span class="keyword">html</span>&gt;</span></span><br><span class="line"><span class="tag">&lt;<span class="name">html</span> <span class="attr">lang</span>=<span class="string">&quot;en&quot;</span>&gt;</span></span><br><span class="line"> <span class="tag">&lt;<span class="name">head</span>&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">meta</span> <span class="attr">charset</span>=<span class="string">&quot;UTF-8&quot;</span>&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">meta</span> <span class="attr">name</span>=<span class="string">&quot;Generator&quot;</span> <span class="attr">content</span>=<span class="string">&quot;EditPlus®&quot;</span>&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">meta</span> <span class="attr">name</span>=<span class="string">&quot;Author&quot;</span> <span class="attr">content</span>=<span class="string">&quot;&quot;</span>&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">meta</span> <span class="attr">name</span>=<span class="string">&quot;Keywords&quot;</span> <span class="attr">content</span>=<span class="string">&quot;&quot;</span>&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">meta</span> <span class="attr">name</span>=<span class="string">&quot;Description&quot;</span> <span class="attr">content</span>=<span class="string">&quot;&quot;</span>&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">title</span>&gt;</span>Document<span class="tag">&lt;/<span class="name">title</span>&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">style</span> <span class="attr">type</span>=<span class="string">&quot;text/css&quot;</span>&gt;</span><span class="language-css"></span></span><br><span class="line"><span class="language-css"></span></span><br><span class="line"><span class="language-css">	<span class="comment">/*整个表格的样式*/</span></span></span><br><span class="line"><span class="language-css">  	<span class="selector-tag">table</span>&#123;</span></span><br><span class="line"><span class="language-css">		<span class="attribute">width</span>: <span class="number">300px</span>;</span></span><br><span class="line"><span class="language-css">		<span class="attribute">height</span>: <span class="number">200px</span>;</span></span><br><span class="line"><span class="language-css">		<span class="attribute">border</span>: <span class="number">1px</span> solid blue;</span></span><br><span class="line"><span class="language-css">		<span class="comment">/*border-collapse属性：对表格的线进行折叠*/</span></span></span><br><span class="line"><span class="language-css">		<span class="attribute">border-collapse</span>: collapse;</span></span><br><span class="line"><span class="language-css">  	&#125;</span></span><br><span class="line"><span class="language-css"></span></span><br><span class="line"><span class="language-css">	<span class="comment">/*鼠标悬停时，让当前行显示#868686这种灰色*/</span></span></span><br><span class="line"><span class="language-css">  	<span class="selector-tag">table</span> <span class="selector-tag">tr</span><span class="selector-pseudo">:hover</span>&#123;</span></span><br><span class="line"><span class="language-css">  		<span class="attribute">background</span>: <span class="number">#868686</span>;</span></span><br><span class="line"><span class="language-css">  	&#125;</span></span><br><span class="line"><span class="language-css"></span></span><br><span class="line"><span class="language-css">	<span class="comment">/*每个单元格的样式*/</span></span></span><br><span class="line"><span class="language-css">  	<span class="selector-tag">table</span> <span class="selector-tag">td</span>&#123;</span></span><br><span class="line"><span class="language-css">  		<span class="attribute">border</span>:<span class="number">1px</span> solid red;</span></span><br><span class="line"><span class="language-css">  	&#125;</span></span><br><span class="line"><span class="language-css"></span></span><br><span class="line"><span class="language-css">  </span><span class="tag">&lt;/<span class="name">style</span>&gt;</span></span><br><span class="line"> <span class="tag">&lt;/<span class="name">head</span>&gt;</span></span><br><span class="line"> <span class="tag">&lt;<span class="name">body</span>&gt;</span></span><br><span class="line"></span><br><span class="line">  <span class="tag">&lt;<span class="name">table</span>&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">tr</span>&gt;</span></span><br><span class="line">	<span class="tag">&lt;<span class="name">td</span>&gt;</span><span class="tag">&lt;/<span class="name">td</span>&gt;</span></span><br><span class="line">	<span class="tag">&lt;<span class="name">td</span>&gt;</span><span class="tag">&lt;/<span class="name">td</span>&gt;</span></span><br><span class="line">	<span class="tag">&lt;<span class="name">td</span>&gt;</span><span class="tag">&lt;/<span class="name">td</span>&gt;</span></span><br><span class="line">	<span class="tag">&lt;<span class="name">td</span>&gt;</span><span class="tag">&lt;/<span class="name">td</span>&gt;</span></span><br><span class="line">  <span class="tag">&lt;/<span class="name">tr</span>&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">tr</span>&gt;</span></span><br><span class="line">	<span class="tag">&lt;<span class="name">td</span>&gt;</span><span class="tag">&lt;/<span class="name">td</span>&gt;</span></span><br><span class="line">	<span class="tag">&lt;<span class="name">td</span>&gt;</span><span class="tag">&lt;/<span class="name">td</span>&gt;</span></span><br><span class="line">	<span class="tag">&lt;<span class="name">td</span>&gt;</span><span class="tag">&lt;/<span class="name">td</span>&gt;</span></span><br><span class="line">	<span class="tag">&lt;<span class="name">td</span>&gt;</span><span class="tag">&lt;/<span class="name">td</span>&gt;</span></span><br><span class="line">  <span class="tag">&lt;/<span class="name">tr</span>&gt;</span></span><br><span class="line">  <span class="tag">&lt;<span class="name">tr</span>&gt;</span></span><br><span class="line">	<span class="tag">&lt;<span class="name">td</span>&gt;</span><span class="tag">&lt;/<span class="name">td</span>&gt;</span></span><br><span class="line">	<span class="tag">&lt;<span class="name">td</span>&gt;</span><span class="tag">&lt;/<span class="name">td</span>&gt;</span></span><br><span class="line">	<span class="tag">&lt;<span class="name">td</span>&gt;</span><span class="tag">&lt;/<span class="name">td</span>&gt;</span></span><br><span class="line">	<span class="tag">&lt;<span class="name">td</span>&gt;</span><span class="tag">&lt;/<span class="name">td</span>&gt;</span></span><br><span class="line">  <span class="tag">&lt;/<span class="name">tr</span>&gt;</span></span><br><span class="line">  <span class="tag">&lt;/<span class="name">table</span>&gt;</span></span><br><span class="line"></span><br><span class="line"> <span class="tag">&lt;/<span class="name">body</span>&gt;</span></span><br><span class="line"><span class="tag">&lt;/<span class="name">html</span>&gt;</span></span><br></pre>

<p>效果：</p>
<p><img  srcset="data:image/svg+xml,%3Csvg%20xmlns='http://www.w3.org/2000/svg'%20viewBox='0%200%20300%20300'%3E%3C/svg%3E" data-src="http://img.smyhvae.com/2015-10-03-css-04.gif" class="lozad post-image"src="http://img.smyhvae.com/2015-10-03-css-04.gif"></p>
<h2 id="我的公众号"><a href="#我的公众号" class="headerlink" title="我的公众号"></a>我的公众号</h2><p>想学习<strong>更多技能</strong>？不妨关注我的微信公众号：<strong>千古壹号</strong>（id：<code>qianguyihao</code>）。</p>
<p>扫一扫，你将发现另一个全新的世界，而这将是一场美丽的意外：</p>
<p><img  srcset="data:image/svg+xml,%3Csvg%20xmlns='http://www.w3.org/2000/svg'%20viewBox='0%200%20300%20300'%3E%3C/svg%3E" data-src="http://img.smyhvae.com/20190101.png" class="lozad post-image"src="http://img.smyhvae.com/20190101.png"></p>

  </div>
  <div>
    
      <div 
        class="post-note note-warning copyright" 
        style="margin-top: 42px">
        <p>
          <span style="font-weight: bold;">作者：</span><a 
            target="_blank" 
            rel="nofollow noopener noreferrer" 
            href="/about">
            zwl5670
          </a>
        </p>
        <p>
          <span style="font-weight: bold;">文章链接：</span><a 
            target="_blank" 
            rel="nofollow noopener noreferrer" 
            href="https://zwl5670.gitee.io/2002/01/01/02-CSS%E5%9F%BA%E7%A1%80/04-CSS%E9%80%89%E6%8B%A9%E5%99%A8%EF%BC%9A%E4%BC%AA%E7%B1%BB/">
            https://zwl5670.gitee.io/2002/01/01/02-CSS%E5%9F%BA%E7%A1%80/04-CSS%E9%80%89%E6%8B%A9%E5%99%A8%EF%BC%9A%E4%BC%AA%E7%B1%BB/
          </a>
        </p>
        <p><span style="font-weight: bold;">版权声明：</span>本博客所有文章除特别声明外，均采用<a target="_blank" rel="noopener" href="https://creativecommons.org/licenses/by-nc-sa/4.0/deed.zh">CC BY-NC-SA 4.0 协议</a>。转载请注明出处！</p>
      </div>
    
  </div>
</article>
<div class="nav">
  
    <div class="nav-item-prev">
      <a 
        href="/2002/01/01/02-CSS%E5%9F%BA%E7%A1%80/02-CSS%E5%B1%9E%E6%80%A7%EF%BC%9A%E8%83%8C%E6%99%AF%E5%B1%9E%E6%80%A7/" 
        class="nav-link">
        <i class="iconfont icon-left nav-prev-icon"></i>
        <div>
          <div class="nav-label">上一篇</div>
          
            <div class="nav-title">02-CSS属性：背景属性 </div>
          
        </div>
      </a>
    </div>
  
  
    <div class="nav-item-next">
      <a 
        href="/2002/01/01/02-CSS%E5%9F%BA%E7%A1%80/05-CSS%E6%A0%B7%E5%BC%8F%E8%A1%A8%E7%9A%84%E7%BB%A7%E6%89%BF%E6%80%A7%E5%92%8C%E5%B1%82%E5%8F%A0%E6%80%A7/" 
        class="nav-link">
        <div>
          <div class="nav-label">下一篇</div>
          
            <div class="nav-title">05-CSS样式表的继承性和层叠性 </div>
          
        </div>
        <i class="iconfont icon-right nav-next-icon"></i>
      </a>
    </div>
  
</div>

<div 
  class="card card-content toc-card" 
  id="mobiletoc">
  <div class="toc-header">
  <i 
    class="iconfont icon-menu" 
    style="padding-right: 2px;">
  </i>目录
</div>
<ol class="toc"><li class="toc-item toc-level-2"><a class="toc-link" href="#%E4%BC%AA%E7%B1%BB%EF%BC%88%E4%BC%AA%E7%B1%BB%E9%80%89%E6%8B%A9%E5%99%A8%EF%BC%89"><span class="toc-text">伪类（伪类选择器）</span></a><ol class="toc-child"><li class="toc-item toc-level-3"><a class="toc-link" href="#%E9%9D%99%E6%80%81%E4%BC%AA%E7%B1%BB%E9%80%89%E6%8B%A9%E5%99%A8%E3%80%81%E5%8A%A8%E6%80%81%E4%BC%AA%E7%B1%BB%E9%80%89%E6%8B%A9%E5%99%A8"><span class="toc-text">静态伪类选择器、动态伪类选择器</span></a></li></ol></li><li class="toc-item toc-level-2"><a class="toc-link" href="#%E8%B6%85%E9%93%BE%E6%8E%A5a%E6%A0%87%E7%AD%BE"><span class="toc-text">超链接a标签</span></a><ol class="toc-child"><li class="toc-item toc-level-3"><a class="toc-link" href="#%E8%B6%85%E9%93%BE%E6%8E%A5%E7%9A%84%E5%9B%9B%E7%A7%8D%E7%8A%B6%E6%80%81"><span class="toc-text">超链接的四种状态</span></a></li><li class="toc-item toc-level-3"><a class="toc-link" href="#%E8%B6%85%E9%93%BE%E6%8E%A5%E7%9A%84%E7%BE%8E%E5%8C%96"><span class="toc-text">超链接的美化</span></a></li></ol></li><li class="toc-item toc-level-2"><a class="toc-link" href="#%E5%8A%A8%E6%80%81%E4%BC%AA%E7%B1%BB%E4%B8%BE%E4%BE%8B"><span class="toc-text">动态伪类举例</span></a></li><li class="toc-item toc-level-2"><a class="toc-link" href="#%E6%88%91%E7%9A%84%E5%85%AC%E4%BC%97%E5%8F%B7"><span class="toc-text">我的公众号</span></a></li></ol>
</div>
            </main>
            <aside class="right-column">
              <div class="sticky-widescreen">
  
  
    <article class="card card-content toc-card">
      <div class="toc-header">
  <i 
    class="iconfont icon-menu" 
    style="padding-right: 2px;">
  </i>目录
</div>
<ol class="toc"><li class="toc-item toc-level-2"><a class="toc-link" href="#%E4%BC%AA%E7%B1%BB%EF%BC%88%E4%BC%AA%E7%B1%BB%E9%80%89%E6%8B%A9%E5%99%A8%EF%BC%89"><span class="toc-text">伪类（伪类选择器）</span></a><ol class="toc-child"><li class="toc-item toc-level-3"><a class="toc-link" href="#%E9%9D%99%E6%80%81%E4%BC%AA%E7%B1%BB%E9%80%89%E6%8B%A9%E5%99%A8%E3%80%81%E5%8A%A8%E6%80%81%E4%BC%AA%E7%B1%BB%E9%80%89%E6%8B%A9%E5%99%A8"><span class="toc-text">静态伪类选择器、动态伪类选择器</span></a></li></ol></li><li class="toc-item toc-level-2"><a class="toc-link" href="#%E8%B6%85%E9%93%BE%E6%8E%A5a%E6%A0%87%E7%AD%BE"><span class="toc-text">超链接a标签</span></a><ol class="toc-child"><li class="toc-item toc-level-3"><a class="toc-link" href="#%E8%B6%85%E9%93%BE%E6%8E%A5%E7%9A%84%E5%9B%9B%E7%A7%8D%E7%8A%B6%E6%80%81"><span class="toc-text">超链接的四种状态</span></a></li><li class="toc-item toc-level-3"><a class="toc-link" href="#%E8%B6%85%E9%93%BE%E6%8E%A5%E7%9A%84%E7%BE%8E%E5%8C%96"><span class="toc-text">超链接的美化</span></a></li></ol></li><li class="toc-item toc-level-2"><a class="toc-link" href="#%E5%8A%A8%E6%80%81%E4%BC%AA%E7%B1%BB%E4%B8%BE%E4%BE%8B"><span class="toc-text">动态伪类举例</span></a></li><li class="toc-item toc-level-2"><a class="toc-link" href="#%E6%88%91%E7%9A%84%E5%85%AC%E4%BC%97%E5%8F%B7"><span class="toc-text">我的公众号</span></a></li></ol>
    </article>
  
  
  <article class="card card-content">
    <div class="recent-posts-card">
  <div class="recent-posts-header">
    <i 
      class="iconfont icon-wenzhang_huaban" 
      style="padding-right: 2px;">
    </i>最近文章
  </div>
  <div class="recent-posts-list">
    
      <div class="recent-posts-item">
        <div class="recent-posts-item-title">2023-03-09</div>
        <a href="/2023/03/09/13-React%E5%9F%BA%E7%A1%80/11-React%20Navive%E5%88%9D%E8%AF%86/"><div class="recent-posts-item-content">11-React Navive初识</div></a>
      </div>
    
      <div class="recent-posts-item">
        <div class="recent-posts-item-title">2023-03-09</div>
        <a href="/2023/03/09/13-React%E5%9F%BA%E7%A1%80/10-AntD%E6%A1%86%E6%9E%B6%E7%9A%84upload%E7%BB%84%E4%BB%B6%E4%B8%8A%E4%BC%A0%E5%9B%BE%E7%89%87%E6%97%B6%E4%BD%BF%E7%94%A8customRequest%E6%96%B9%E6%B3%95%E8%87%AA%E5%AE%9A%E4%B9%89%E4%B8%8A%E4%BC%A0%E8%A1%8C%E4%B8%BA/"><div class="recent-posts-item-content">10-AntD框架的upload组件上传图片时使用customRequest方法自定义上传行为</div></a>
      </div>
    
      <div class="recent-posts-item">
        <div class="recent-posts-item-title">2023-03-09</div>
        <a href="/2023/03/09/13-React%E5%9F%BA%E7%A1%80/09-AntD%E6%A1%86%E6%9E%B6%E7%9A%84upload%E7%BB%84%E4%BB%B6%E4%B8%8A%E4%BC%A0%E5%9B%BE%E7%89%87%E6%97%B6%E9%81%87%E5%88%B0%E7%9A%84%E4%B8%80%E4%BA%9B%E5%9D%91/"><div class="recent-posts-item-content">09-AntD框架的upload组件上传图片时遇到的一些坑</div></a>
      </div>
    
      <div class="recent-posts-item">
        <div class="recent-posts-item-title">2023-03-09</div>
        <a href="/2023/03/09/13-React%E5%9F%BA%E7%A1%80/08-Ant%20Design%E7%9A%84%E5%9F%BA%E6%9C%AC%E4%BD%BF%E7%94%A8/"><div class="recent-posts-item-content">08-Ant Design的基本使用</div></a>
      </div>
    
  </div>
</div>
  </article>
  
  
</div>
            </aside>
          </div>
        </div>
      </div>
    </div>
     
    <footer class="footer">
  <div class="footer-container">
    <div>
      <div class="footer-dsc">
        <span>
          Copyright ©
          
            2023
          
          
        </span>
        &nbsp;
        <a 
          href="/" 
          class="footer-link">
          前端面试
        </a>
      </div>
    </div>

    
      <div class="footer-dsc">
        
          Powered by
          <a 
            href="https://hexo.io/" 
            class="footer-link" 
            target="_blank" 
            rel="nofollow noopener noreferrer">
            &nbsp;Hexo
          </a>
        
        
          <span>&nbsp;|&nbsp;</span>
        
        
          Theme -
          <a 
            href="https://github.com/theme-kaze" 
            class="footer-link" 
            target="_blank"
            rel="nofollow noopener noreferrer">
            &nbsp;Kaze
          </a>
        
      </div>
    
    
    
    
</footer>
 
    
  <a 
    role="button" 
    id="scrollbutton" 
    class="basebutton" 
    aria-label="回到顶部">
    <i class="iconfont icon-arrowleft button-icon"></i>
  </a>

<a 
  role="button" 
  id="menubutton"
  aria-label="menu button"
  class="basebutton">
  <i class="iconfont icon-menu button-icon"></i>
</a>
<a 
  role="button" 
  id="popbutton" 
  class="basebutton" 
  aria-label="控制中心">
  <i class="iconfont icon-expand button-icon"></i>
</a>
<a 
  role="button" 
  id="darkbutton" 
  class="basebutton darkwidget" 
  aria-label="夜色模式">
  <i class="iconfont icon-weather button-icon"></i>
</a>
<a 
  role="button" 
  id="searchbutton" 
  class="basebutton searchwidget" 
  aria-label="搜索">
  <i class="iconfont icon-search button-icon"></i>
</a> 
     
     
     
      <script>
  var addImgLayout = function () {
    var img = document.querySelectorAll('.post-content img')
    var i
    for (i = 0; i < img.length; i++) {
      var wrapper = document.createElement('a')
      wrapper.setAttribute('href', img[i].getAttribute('data-src'))
      wrapper.setAttribute('aria-label', 'illustration')
      wrapper.style.cssText =
        'width: 100%; display: flex; justify-content: center;'
      if (img[i].alt) wrapper.dataset.caption = img[i].alt
      wrapper.dataset.nolink = true
      img[i].before(wrapper)
      wrapper.append(img[i])
      var divWrap = document.createElement('div')
      divWrap.classList.add('gallery')
      wrapper.before(divWrap)
      divWrap.append(wrapper)
    }
    baguetteBox.run('.gallery')
  }
</script>
<script>
  loadScript(
    "/js/lib/lightbox/baguetteBox.min.js",
    addImgLayout
  )
</script>
 
     
     
    <script src="/js/main.js"></script> 
     
    
      <script>
        var addLazyload = function () {
          var observer = lozad('.lozad', {
            load: function (el) {
              el.srcset = el.getAttribute('data-src')
            },
            loaded: function (el) {
              el.classList.add('loaded')
            },
          })
          observer.observe()
        }
      </script>
      <script>
        loadScript('/js/lib/lozad.min.js', addLazyload)
      </script>
    
    <script src="//instant.page/5.1.0" type="module"
      integrity="sha384-by67kQnR+pyfy8yWP4kPO12fHKRLHZPfEsiSXR8u2IKcTdxD805MGUXBzVPnkLHw"></script>
    
    
  </body>
</html>
